The present invention generally relates to a moldable substrate which exhibits surface barrier properties as well as thermal and sound insulation properties.
The transportation industry currently uses moldable materials in a variety of applications which require both thermal and sound insulating performance features. In a number of applications the primary purpose of these materials is to act as a heat shield to vehicle components or occupants. Examples of heat shielding parts would include vehicle hood liners, firewall barriers, automotive transmission tunnel insulators, etc. Often a heat shield will have a moldable foam core, a resinated fiberglass core, a resinated cotton shoddy core, or other to give the shield volume and aid in the in absorption of heat and sound. The heat shield may also include a textile shell material enclosing the moldable core. The shell material gives the composite a desired aesthetic appearance and can provide an oil and water impermeable surface.
The present invention uses a blended synthetic fiber core to provide the heat shield with volume and moldability. A blend of common synthetic fibers and fibers of partially oxidized polyacrylonitrile are used to construct a low weight skin that is subsequently attached to the core on one or both sides. The invention has superior molding process performance, superior sound and heat absorptive performance, and the potential to be recycled. All of these benefits were achieved at competitive costs and weight to the existing products.